Open AccessPlasmonic wavy surface for ultrathin semiconductor black absorbers
Author(s) -
Peng Tang,
Guiqiang Liu,
Xiaoshan Liu,
Guolan Fu,
Zhengqi Liu,
Junqiao Wang
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.402234
Subject(s) - materials science , plasmon , optoelectronics , optics , absorption (acoustics) , semiconductor , polarization (electrochemistry) , indium gallium nitride , surface plasmon , indium tin oxide , germanium , wavelength , layer (electronics) , nanotechnology , silicon , physics , chemistry , composite material , gallium nitride
In this work, we propose and demonstrate a near-unity light absorber in the ultra-violet to near-infrared range (300-1100 nm) with the average efficiency up to 97.7%, suggesting the achievement of black absorber. The absorber consists of a wavy surface geometry, which is formed by the triple-layer of ITO (indium tin oxide)-Ge (germanium)-Cu (copper) films. Moreover, the minimal absorption is even above 90% in the wide wavelength range from 300 nm to 1015 nm, suggesting an ultra-broadband near-perfect absorption window covering the main operation range for the conventional semiconductors. Strong plasmonic resonances and the near-field coupling effects located in the spatially geometrical structure are the key contributions for the broadband absorption. The absorption properties can be well maintained during the tuning of the polarization and incident angles, indicating the high tolerance in complex electromagnetic surroundings. These findings pave new ways for achieving high-performance optoelectronic devices based on the light absorption over the full-spectrum energy gap range.